Outphasing transmitters may be used in stations of wireless communication systems such as, for example, base stations, mobile stations of cellular communication system and/or mobile unit and access point of wireless local area network (WLAN) and/or other types of wireless communication systems, if desired.
Outphasing techniques may combine two nonlinear radio frequency (RF) power amplifiers (PA's) into a linear power amplifier system. The two PA's may be driven with signals of different phases, and the phases may be controlled to provide an output signal with the desired amplitude.
The linear power amplifier system may include a combiner to combine the signal provided by the two nonlinear PA's. The combiner may include two transmission line couplers with shunt reactance. The power and efficiency of the outphasing transmitter may depend on the characteristics of the components and the architecture of the two transmission line couplers with shunt reactance.
It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.